Liquid ejecting head and flow passage structure

ABSTRACT

A flow passage structure includes a flow passage member that constitutes a portion of a wall surface of a liquid storage chamber; a flexible film that is laminated on the flow passage member and constitutes a portion of the wall surface of the liquid storage chamber; a sealing body that is laminated on a side opposite to the flow passage member with the flexible film interposed therebetween and forms a space in which the flexible film is exposed; communication passages that are formed in a region around the liquid storage chamber in the sealing body and causes the space to communicate with an atmosphere in a case where the sealing body is seen in a plan view from a direction in which the flow passage member and the flexible film are laminated; and a support portion that supports the flexible film in the communication passage.

BACKGROUND 1. Technical Field

The present invention relates to a technique of ejecting liquid such asink.

2. Related Art

In the related art, a liquid ejecting head that ejects liquid such asink supplied from a liquid storage chamber to a pressure chamber from anozzle by generating pressure change in the pressure chamber has beenproposed. In this type of liquid ejecting head, when pressurefluctuation occurs in the liquid storage chamber by liquid introductioninto the liquid storage chamber and pressure change in the pressurechamber, the pressure may be transferred to the pressure chamber, whichmay cause an ejection failure of the liquid. For this reason, forexample, in the liquid ejecting head disclosed in JP-A-2015-057315, arecessed portion constituting a liquid storage chamber (manifold) isclosed and sealed with a flexible film (film) so that a portion of awall surface is constituted of the flexible film. According to thisconfiguration, the ejection failure is suppressed by absorbing thepressure fluctuation of the liquid storage chamber by bending theflexible film. Furthermore, in JP-A-2015-057315, a space is formed inwhich the flexible film bends on a side opposite to the liquid storagechamber with the flexible film interposed therebetween, and the space iscommunicated with an atmospheric vent (through-hole) via a communicationpassage extending around the liquid storage chamber. With thisconfiguration, the air in the space in which the flexible film bends canenter and exit from the atmospheric vent according to the movement ofthe flexible film, so that the movement of the flexible film isfacilitated.

However, in the configuration in which a communication passage thatcommunicates a space in which a flexible film bends to the atmosphere isprovided as in JP-A-2015-057315, since the cross-sectional area of thecommunication passage becomes smaller as the width of the communicationpassage becomes narrower, the air resistance increases, and thereby, itbecomes difficult for the air in the space in which the flexible filmbends to enter and exit from the atmosphere via the communicationpassage. Therefore, the flexible film becomes difficult to move and theeffect of absorbing the pressure fluctuation of the liquid storagechamber is deteriorated. On the contrary, as the width of thecommunication passage becomes wider, since the flexible film exposedinto the communication passage easily bends in the communicationpassage, the sealing property between the flow passage member and theflexible film is deteriorated in the region around the liquid storagechamber, and leak of liquid may occur.

SUMMARY

An advantage of some aspects of the invention is to suppressdeterioration of sealing property between a flow passage member and aflexible film around a liquid storage chamber while increasing an effectof absorbing pressure fluctuation of the liquid storage chamber.

According to an aspect of the invention, there is provided a flowpassage structure including: a flow passage member that constitutes aportion of a wall surface of a liquid storage chamber; a flexible filmthat is laminated on the flow passage member and constitutes a portionof the wall surface of the liquid storage chamber; a sealing body thatis laminated on a side opposite to the flow passage member with theflexible film interposed therebetween and forms a space in which theflexible film is exposed; communication passages that are formed in aregion around the liquid storage chamber in the sealing body and causesthe space to communicate with an atmosphere in a case where the sealingbody is seen in a plan view from a direction in which the flow passagemember and the flexible film are laminated; and a support portion thatsupports the flexible film in the communication passage. In this case,since the flexible film is supported by the support portion in thecommunication passage formed in the region around the liquid storagechamber that seals the flow passage member and the flexible film in thesealing body, even if the width of the communication passage isincreased, it is difficult to bond the flow passage member with theflexible film exposed into the communication passage bends so that thedeterioration of the sealing property can be suppressed.

“A region around the liquid storage chamber” is a region outside theliquid storage chamber in a plan view of the sealing body. For example,in a case where an opening penetrating the flow passage memberconstitutes a portion of the liquid storage chamber, a regionoverlapping the flow passage member constituting the opening correspondsto “a region around the liquid storage chamber”. The flexible film maynot adhere to the flow passage member immediately above the supportportion.

In the flow passage structure, it is preferable that in a cross sectionincluding the support portion among cross sections of the communicationpassages that intersect with a direction in which the communicationpassage extends, an area of a portion occupied by the support portion besmaller than an area of the other portions. In this case, since the areaof the portion occupied by the support portion is smaller than the areaof the other portions, the air resistance by the support portion can bereduced in the cross section including the support portion among thecross sections of the communication passage interesting with thedirection in which the communication passage extends. For this reason,the air in the space in which the flexible film bends easily enters andexits from the atmosphere via the communication passage, and themovement of the flexible film exposed in the space of the sealing bodyis facilitated, so that the effect of absorbing the pressure fluctuationof the liquid storage chamber can be increased. In this case, it ispossible to suppress deterioration of the sealing property between theflow passage member and the flexible film around the liquid storagechamber while increasing the effect of absorbing the pressurefluctuation of the liquid storage chamber.

In the flow passage structure, it is preferable that the communicationpassage communicate with the atmosphere via an atmospheric ventdistanced from the liquid storage chamber, and a width of thecommunication passage in the cross section of the communication passagethat intersects with the direction in which the communication passageextends be larger than a diameter of the atmospheric vent. In this case,since the width of the communication passage in the cross section of thecommunication passage which intersects the direction in which thecommunication passage extends is larger than the diameter of theatmospheric vent, the air resistance in the communication passage in thedirection in which the communication passage extends can be reduced ascompared with the case where the width of the communication passage issmaller than the diameter of the atmospheric vent.

In the flow passage structure, it is preferable that the atmosphericvent be a through-hole formed in the flexible film. In this case, sincethe width of the communication passage is larger than the diameter ofthe atmospheric vent formed in the flexible film, the air resistance inthe communication passage in the direction in which the communicationpassage extends can be reduced as compared with the configuration inwhich the width of the communication passage is smaller than thediameter of the atmospheric vent.

In the flow passage structure, it is preferable that the atmosphericvent be formed in the flow passage member. In this case, since theatmospheric vent is formed in a flow passage member having a liquidstorage chamber, it is easy to form the atmospheric vent away from theliquid storage chamber, so that it is possible to facilitate the routingof the communication passage. Moreover, since the width of thecommunication passage is larger than the diameter of the atmosphericvent formed in the flow passage member, the air resistance in thecommunication passage in the direction in which the communicationpassage extends can be reduced as compared with the configuration inwhich the width of the communication passage is smaller than thediameter of the atmospheric vent.

In the flow passage structure, it is preferable that the support portionbe an island portion that is disposed in the communication passage. Inthis case, since the support portion is the island portion disposed inthe communication passage, depending on the number, arrangement andshape of the island portions, the area of the portion occupied by thesupport portion can be made smaller than the area of the other portions,so that it is easy to reduce the air resistance in the communicationpassage.

In the flow passage structure, it is preferable that a plurality of theisland portions be arranged side by side in a direction in which thecommunication passage extends. In this case, since a plurality of islandportions are arranged side by side in the direction in which thecommunication passage extends, and the plurality of island portionsoverlap when viewed from that direction, the resistance in the directionin which the communication passage extends, that is, the directionthrough which air passes can be reduced.

In the flow passage structure, it is preferable that the support portionbe a rail portion that projects into the communication passage from oneor both sides of side surfaces of the communication passage facing eachother. In this case, since the support portion is a rail portionprojecting from one or both sides of side surfaces facing each other ofthe communication passage into the communication passage, depending onthe number, arrangement, and shape of the rail portion, the area of theportion occupied by the support portion can be made smaller than thearea of other portions, so that it is easy to reduce the air resistancein the communication passage.

In the flow passage structure, it is preferable that the width of thecommunication passage be ½ or more of a maximum width of a cross sectionof the space among cross sections of the communication passages thatintersect with a direction in which the communication passage extends.In this case, by setting the width of the communication passage to be ½or more of the maximum width of the space in the cross section of thecommunication passage which intersects the direction in which thecommunication passage extends, the air resistance in the communicationpassage in the direction in which the communication passage extends canbe greatly reduced.

In the flow passage structure, it is preferable that the sealing body beconstituted of a support plate that is laminated on the flexible filmand a fixation plate that is laminated on the support plate on a sideopposite to the flexible film, and the support portion support theflexible film that protrudes from the fixation plate toward the flexiblefilm. In this case, since the support portion protrudes from thefixation plate toward the flexible film to support the flexible film, itis possible to suppress bending of the flexible film from the flowpassage member into the communication passage.

In the flow passage structure, it is preferable that in a plan view ofthe sealing body, the communication passage be formed in a regioncorresponding to one end of the liquid storage chamber in the sealingbody.

In the flow passage structure, it is preferable that a plurality of theliquid storage chambers be formed in the flow passage member, aplurality of the spaces each corresponding to the plurality of liquidstorage chambers be formed in the sealing body, and the communicationpassage communicate with each of the spaces.

According to another aspect of the invention, there is provided a liquidejecting head including: the flow passage structure according to anaspect; and a nozzle that ejects liquid supplied from the liquid storagechamber. In this case, it is possible to provide a liquid ejecting headprovided with a flow passage structure capable of suppressingdeterioration of the sealing property between the flow passage memberand the flexible film around the liquid storage chamber while increasingthe effect of absorbing the pressure fluctuation of the liquid storagechamber.

According to still another aspect of the invention, there is provided aliquid ejecting apparatus including: the liquid ejecting head accordingto another aspect; and a control device that causes the liquid ejectinghead to eject liquid.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanyingdrawings, wherein like numbers reference like elements.

FIG. 1 is a structural view of a liquid ejecting apparatus according toa first embodiment.

FIG. 2 is an exploded perspective view of a liquid ejecting head.

FIG. 3 is a sectional view taken along line III-III of the liquidejecting head shown in FIG. 2.

FIG. 4 is a partial cross-sectional perspective view of the liquidejecting head.

FIG. 5 is a plan view of a compliance plate constituting a portion of aflow passage structure.

FIG. 6 is an enlarged view of VI portion shown in FIG. 5.

FIG. 7 is a plan view of a compliance plate according to a firstcomparative example.

FIG. 8 is a sectional view taken along line VIII-VIII shown in FIG. 7.

FIG. 9 is a graph showing pressure transition of a liquid storagechamber in a specific print pattern.

FIG. 10 is a plan view showing a configuration of a compliance plateaccording to a second comparative example.

FIG. 11 is a sectional view taken along line XI-XI in FIG. 10.

FIG. 12 is a sectional view taken along line XII-XII shown in FIG. 10.

FIG. 13 is an operation explanatory view of the compliance plate of thefirst embodiment.

FIG. 14 is a sectional view taken along line XIV-XIV shown in FIG. 13.

FIG. 15 is a sectional view taken along line XV-XV shown in FIG. 13.

FIG. 16 is a sectional view of the compliance plate according to a firstmodification example.

FIG. 17 is a sectional view of the compliance plate according to asecond modification example.

FIG. 18 is a plan view of the compliance plate according to a thirdmodification example.

FIG. 19 is a plan view of the compliance plate according to a fourthmodification example.

FIG. 20 is a plan view showing a configuration of the compliance plateaccording to a fifth modification example.

FIG. 21 is a sectional view taken along line XXI-XXI in FIG. 20.

FIG. 22 is a plan view showing a compliance plate according to a secondembodiment.

DESCRIPTION OF EXEMPLARY EMBODIMENTS First Embodiment

FIG. 1 is a partial structural view of a liquid ejecting apparatus 10according to a first embodiment of the invention. The liquid ejectingapparatus 10 of the first embodiment is an ink jet type printingapparatus that ejects ink as an example of liquid onto a medium 11 suchas printing paper. The liquid ejecting apparatus 10 shown in FIG. 1includes a control device 12, a transport mechanism 15, a carriage 18,and a liquid ejecting head 20. The liquid ejecting apparatus 10 ismounted with a liquid container 14 for storing ink.

The liquid container 14 is an ink tank type cartridge made of abox-shaped container attachable and detachable to and from the main bodyof the liquid ejecting apparatus 10. The liquid container 14 is notlimited to a box-shaped container, and may be an ink pack type cartridgemade of a bag-shaped container. Ink is stored in the liquid container14. The ink may be black ink, or color ink. The ink stored in the liquidcontainer 14 is pressurized and fed to the liquid ejecting head 20 by apump (not shown).

The control device 12 integrally controls each element of the liquidejecting apparatus 10. The transport mechanism 15 transports the medium11 in a Y direction under the control of the control device 12. Theliquid ejecting head 20 ejects ink supplied from the liquid container 14from each of a plurality of nozzles N onto the medium 11 under thecontrol of the control device 12.

The liquid ejecting head 20 is installed in the carriage 18. In FIG. 1,a case where a single liquid ejecting head 20 is installed in thecarriage 18 is exemplified. However, the invention is not limitedthereto, and a plurality of liquid ejecting heads 20 may be installed inthe carriage 18. The control device 12 reciprocates the carriage 18 inan X direction intersecting (orthogonal in FIG. 1) in the Y direction. Adesired image is formed on a surface of the medium 11 by the liquidejecting head 20 ejecting ink onto the medium 11 in parallel with therepetition of the transport of the medium 11 and the reciprocation ofthe carriage 18. A plurality of liquid ejecting heads 20 may beinstalled in the carriage 18. A direction perpendicular to an X-Y plane(plane parallel to the surface of the medium 11) is defined as a Zdirection.

Liquid Ejecting Head

FIG. 2 is an exploded perspective view of the liquid ejecting head 20.FIG. 3 is a sectional view taken along line III-III of the liquidejecting head 20 shown in FIG. 2. As shown in FIGS. 2 and 3, the liquidejecting head 20 is configured by fixing (bonding) a case member 40 to ahead body 30 having an ejection surface on which nozzles N for ejectingink are formed. The head body 30 has a structure in which a flow passagemember 32 is provided, a nozzle plate 62 on which the plurality ofnozzles N are formed, a compliance plate 50, and a fixation plate 56 arelaminated on one side (surface on the positive side in the Z direction)thereof and a laminated portion 38 including a pressure chambersubstrate 382 is laminated on the other side (surface on the negativeside in the Z direction) thereof. Each element of the head body 30 ismutually fixed by, for example, an adhesive. The flow passage member 32,the compliance plate 50, and the fixation plate 56 of the presentembodiment constitute a flow passage structure.

The nozzle plate 62 is a flat plate material constituting the ejectionsurface on which the plurality of nozzles N are arranged in the Ydirection. The nozzle plate 62 is made of, for example, a siliconmaterial. The plurality of nozzles N are formed of two rows of nozzlerows L1 and L2. Each of the nozzle rows L1 and L2 is an aggregation ofthe plurality of nozzles N arranged along the Y direction. Thearrangement of the nozzle rows L1 and L2 is not limited to the one shownin the present embodiment. For example, each of the nozzle rows L1 andL2 may be arranged by being shifted in the Y direction. Moreover, thenumber of nozzle rows formed on the nozzle plate 62 is not limited totwo, and may be one.

In the liquid ejecting head 20 according to the present embodiment, astructure corresponding to the nozzle row L1 (left portion of FIG. 3)and a structure corresponding to the nozzle row L2 (right portion ofFIG. 3) are formed substantially in line symmetrically with respect to avirtual line O-O in the X direction, and both structures aresubstantially common. Therefore, in the following description, theattention is focused on the structure corresponding to the nozzle row L1(left portion from virtual line O-O of FIG. 3), and the description ofthe elements corresponding to the nozzle row L2 will be omitted for thesake of convenience. FIG. 4 is a partial cross-sectional perspectiveview of the structure corresponding to the nozzle row L1. In FIG. 4, aplurality of pressure chambers SC are indicated by broken line.

The flow passage member 32 shown in FIGS. 2 to 4 is a flat flow passagesubstrate constituting a flow passage of ink. The flow passage member 32is made of, for example, a silicon material. A second liquid storagechamber 34 and a plurality of nozzle side communication flow passages326 are formed in the flow passage member 32. The second liquid storagechamber 34 includes an inflow port 342 through which ink flows and aplurality of supply side communication flow passages 344. The pluralityof supply side communication flow passages 344 and the plurality ofnozzle side communication flow passages 326 are through-holes formed foreach of the nozzles N, and the second liquid storage chamber 34 is anopening common to the plurality of nozzles N.

The laminated portion 38 is constituted by laminating the pressurechamber substrate 382 forming the pressure chambers SC communicatingwith the nozzles N, a vibration plate 384, and a protective plate 386 inthis order. However, the invention is not limited to such aconfiguration, and the laminated portion 38 may be constituted withoutthe protective plate 386. Moreover, the vibration plate 384 and thepressure chamber substrate 382 may be formed integrally. A plurality ofopening portions 383 constituting the pressure chambers SC (cavities)communicating with each of the nozzles N are formed in the pressurechamber substrate 382. The pressure chamber substrate 382 is made of,for example, a silicon material similar to the flow passage member 32.

The vibration plate 384 is installed on a surface of the pressurechamber substrate 382 opposite to the flow passage member 32. Thevibration plate 384 is an elastically vibratable flat plate material.The vibration plate 384 and the flow passage member 32 are opposed toeach other with a gap therebetween inside each of the opening portions383 formed on the pressure chamber substrate 382. The pressure chambersSC that generate pressure for ejecting ink from each of the nozzles N isconstituted by a space interposed between the flow passage member 32 andthe vibration plate 384 inside the opening portions 383 of the pressurechamber substrate 382. Each of the supply side communication flowpassages 344 of the flow passage member 32 communicates the secondliquid storage chamber 34 described later with the pressure chambers SC,and each of the nozzle side communication flow passages 326 of the flowpassage member 32 communicates the pressure chambers SC with the nozzlesN.

A plurality of piezoelectric elements 385 corresponding to differentnozzles N (pressure chambers SC) are formed on the surface of thevibration plate 384 opposite to the pressure chamber substrate 382. Eachof the piezoelectric elements 385 is a driving element in which apiezoelectric substance is interposed between electrodes facing eachother. Each of the piezoelectric elements 385 individually vibrates by adrive signal supplied from the control device 12. The protective plate386 is an element for protecting each of the piezoelectric elements 385,and is fixed on a surface of the pressure chamber substrate 382(vibration plate 384) by, for example, an adhesive. Each of thepiezoelectric elements 385 is stored in a recessed portion 387 formed ona surface of the protective plate 386 on the vibration plate 384 side.When each of the piezoelectric elements 385 vibrates according to thedrive signal supplied from the control device 12, the vibration plate384 vibrates in interlocking with the piezoelectric elements 385. As aresult, the pressure of ink inside the pressure chambers SC fluctuatesand the ink is ejected from the nozzles N. In this manner, thepiezoelectric elements 385 function as pressure generating elements thatfluctuate the pressure inside the pressure chambers SC to eject the inkinside the pressure chambers SC from the nozzles N. The piezoelectricelements 385 are connected with the control device 12 via a flexibleprinted cable (FPC: flexible printed circuit), a chip on film (COF) (notshown), or the like.

A surface of the case member 40 on a positive side in the Z direction(hereinafter, referred to as “bonding surface”) is fixed on a surface ofthe flow passage member 32 on a negative side of the Z direction by anadhesive, for example. The case member 40 is made of a molding resinmaterial such as a plastic material. In a case where the case member 40is made of a molding resin material, it can be molded integrally by aninjection molding of the molding resin material. The case member 40 is acase for storing the ink supplied from the plurality of pressurechambers SC, and has a structure in which a first liquid storage chamber42 that is communicated with the second liquid storage chamber 34 by theinflow port 342 as an opening portion. The first liquid storage chamber42 communicates with an inlet 43 for introducing the ink.

Such a second liquid storage chamber 34 and first liquid storage chamber42 are common spaces over the plurality of nozzles N, and store the inksupplied from the liquid container 14 in the inlet 43. The second liquidstorage chamber 34 is formed of a space elongated in the Y direction.The second liquid storage chamber 34 of the present embodiment has ashape in which the flow passage is expanded from the inflow port 342side toward the supply side communication flow passages 344 (outflowport) side. The plurality of pressure chambers SC are arranged in onedirection (Y direction), and the plurality of supply side communicationflow passages 344 are arranged along the arrangement of the plurality ofpressure chambers SC in the Y direction.

As shown in FIG. 4, the ink flowing into the second liquid storagechamber 34 from the first liquid storage chamber 42 is branched by theplurality of supply side communication flow passages 344, is supplied toeach of the pressure chambers SC in parallel, and is charged. Then, theink passes through the nozzle side communication flow passages 326 andthe nozzles N from the pressure chambers SC due to the pressurefluctuation in accordance with the vibration of the vibration plate 384and is ejected to the outside. That is, the pressure chambers SCfunction as spaces that generate pressure for ejecting ink from thenozzles N, and the second liquid storage chamber 34 and the first liquidstorage chamber 42 function as a liquid storage chamber SR (reservoir ormanifold) for storing the ink supplied to the plurality of pressurechambers SC.

Flow Passage Structure

FIG. 5 is a plan view of the compliance plate 50 constituting a portionof the flow passage structure of the first embodiment as seen from the Zdirection. FIG. 6 is an enlarged view of VI portion shown in FIG. 5. Asshown in FIGS. 3 and 5, the compliance plate 50 of the presentembodiment is an element for suppressing the pressure fluctuation of inkinside the liquid storage chamber SR, and includes a flexible film 52(compliance substrate) and a support plate 54. The flexible film 52 is aflexible member formed in a film shape, and constitutes a portion of awall surface (specifically, bottom surface) of the liquid storagechamber SR. For example, polyphenylene sulfide (PPS), aromatic polyamide(aramid), stainless steel (SUS), and the like can be used as a materialof the flexible film 52 as long as the flexible film 52 can bend. Thecase where the second liquid storage chamber 34 corresponding to thenozzle row L1 and the second liquid storage chamber 34 corresponding tothe nozzle row L2 are sealed with a single flexible film 52 has beendescribed in FIG. 3. However, the invention is not limited thereto, andboth second liquid storage chambers 34 may be sealed with separateflexible films 52. The flexible film 52 is laminated in the Z directionof the flow passage member 32 and the support plate 54 is laminated on aside opposite to the flow passage member 32 interposing the flexiblefilm 52 therebetween. The Z direction of the present embodimentcorresponds to a lamination direction of the flow passage member 32, theflexible film 52, and the support plate 54.

As shown in FIG. 5, the support plate 54 is a flat plate formed of ahighly rigid material such as stainless steel (SUS), and supports theflexible film 52 so that the liquid storage chamber SR is sealed withthe flexible film 52. In the support plate 54, an opening portion 541constituting a space where the flexible film 52 is exposed is formed ina compliance region A overlapping the liquid storage chamber SR in aplan view (plan view from Z direction). The compliance region A (regionof the flexible film 52 to which the opening portion 541 is exposed) isa region that has a compliance function capable of absorbing thepressure fluctuation inside the liquid storage chamber SR by deformation(bending vibration) of the flexible film 52. In a region B around theliquid storage chamber SR not overlapping the liquid storage chamber SRin a plan view, the flow passage member 32 and the flexible film 52adhere to each other. Accordingly, the flow passage member 32 and theflexible film 52 are sealed so that the ink does not leak from theliquid storage chamber SR. A space (inner space of the opening portion541) constituted by the opening portion 541 of the support plate 54communicates with the atmosphere via a communication passage 544, andfunctions as a compliance space SG for deforming the flexible film 52 soas to absorb the pressure fluctuation inside the liquid storage chamberSR.

The compliance plate 50 is fixed on the fixation plate 56. The fixationplate 56 is formed into a predetermined shape with a highly rigidmaterial such as stainless steel. A plurality of opening portions 622corresponding to each nozzle plate 62 are formed in the fixation plate56, respectively. An opening portion 522 corresponding to the pluralityof opening portions 622 is formed in the flexible film 52, and anopening portion 542 corresponding to the plurality of opening portions622 is formed in the support plate 54. The support plate 54 of thecompliance plate 50 is fixed on the fixation plate 56 so that the nozzleplate 62 is exposed from the opening portions 522, 542, and 562. A spaceinside the opening portions 522, 542, and 562 (specifically, a gapbetween the inner peripheral surfaces of the opening portions 522, 542,and 562 and an outer peripheral surface of the nozzle plate 62) isfilled with a filler formed of, for example a resin material.

The positive side of the opening portion 541 of the support plate 54 inthe Z direction is sealed with the fixation plate 56 by fixing thesupport plate 54 on the fixation plate 56, and the space interposedbetween the flexible film 52 and the fixation plate 56 inside theopening portion 541 becomes the above-described compliance space SG. Thesupport plate 54 and the fixation plate 56 of the present embodimentfunction as a sealing body in which a space (compliance space SG) wherethe flexible film 52 is exposed is formed. In the present embodiment,the case where the sealing body is formed with the support plate 54 andthe fixation plate 56 as separate bodies is exemplified. However, theinvention is not limited thereto, and a sealing body may be formed byintegrating the support plate 54 and the fixation plate 56 together.According to the compliance plate 50 constituted as described above,even if pressure fluctuation occurs in the liquid storage chamber SR,the pressure fluctuation can be absorbed by deformation of the flexiblefilm 52. Since the opening portion 541 of the support plate 54communicates with the atmosphere via the communication passage 544, theair inside the opening portion 541 can enter and exit from theatmosphere via the communication passage 544 according to the movementof the flexible film 52, so that the movement of the flexible film 52 isfacilitated. The fixation plate 56 and the nozzle plate 62 may be formedintegrally. In this case, the nozzles N may be formed on the fixationplate 56, and the opening portion 541 may be sealed with the nozzleplate 62.

Communication Passage

Here, a specific configuration example of the communication passage 544that communicates the above-described opening portion 541 of the supportplate 54 with the atmosphere will be described with reference to thedrawings. As shown in FIGS. 5 and 6, the communication passage 544 isformed in the region B around the liquid storage chamber SR that sealsthe flow passage member 32 and the flexible film 52 of the support plate54. The region B is a non-compliance region in which the opening portion541 is not overlapping the liquid storage chamber SR. In the flexiblefilm 52, the flow passage member 32 and the flexible film 52 are sealedaround the liquid storage chamber SR by adhering to the flow passagemember 32 at the region B. An atmospheric vent HA is formed at aposition away from the liquid storage chamber SR in the region B in adirection of a nozzle row (negative side of Y direction in FIG. 5) inthe flow passage member 32 and the flexible film 52. As shown in FIG. 2,the atmospheric vent HA is a through-hole that penetrates the flowpassage member 32, the flexible film 52, and the case member 40 andcommunicates the communication passage 544 of the support plate 54 withthe atmosphere. The atmospheric vent HA is disposed away from the liquidstorage chamber SR in the negative side of the Y direction, and thecommunication passage 544 extends from the opening portion 541 in thenegative side of the Y direction and communicates with the atmosphericvent HA. As described above, the communication passage 544 of thepresent embodiment is an air passage that continues to the openingportion 541 of the support plate 54, and communicates the openingportion 541 with the atmospheric vent HA. Since the atmospheric vent HAis formed in the flow passage member 32 in which the liquid storagechamber SR exists, the atmospheric vent HA can be easily formed awayfrom the liquid storage chamber SR, and it is possible to facilitate therouting of the communication passage 544.

Since the cross-sectional area of the communication passage 544 thatintersects with the direction (Y direction) in which the communicationpassage 544 extends becomes smaller as the width of the cross section isnarrower, the air resistance increases, so that the air in the openingportion 541 hardly enters and exits from the atmospheric vent HA via thecommunication passage 544 when the flexible film 52 bends. Therefore,the flexible film 52 becomes difficult to move and the effect ofabsorbing the pressure fluctuation of the liquid storage chamber SR isdeteriorated.

As a configuration of suppressing the air resistance of thecommunication passage 544, it is also conceivable to increase thethickness of the support plate 54 to secure the height of the crosssection of the communication passage 544 sufficiently. However, in theconfiguration that the thickness of the support plate 54 is increased,since a surface of the fixation plate 56 approaches the medium 11, apossibility of the medium 11 coming into contact with the surface of thefixation plate 56 increases. On the other hand, it is possible to setthe position of the liquid ejecting head 20 in the Z direction to securea predetermined gap between the surface of the fixation plate 56 and themedium 11 in order to suppress the contact of the medium 11 with respectto the fixation plate 56. However, with the above-describedconfiguration, the distance between the medium 11 and the nozzle plate62 increases. Therefore, an error tends to occur at the position wherethe liquid ejected from the nozzles N land on the surface of the medium11, and as a result, there is a possibility that the print quality maybe deteriorated. Considering above circumstances, the configuration ofreducing the air resistance by sufficiently securing the width of thecommunication passage 544 is more preferable than the configuration ofsecuring the height of the communication passage 544.

FIGS. 7 and 8 are views showing a configuration of a compliance plate50′ according to a first comparative example of the first embodiment.FIG. 7 is a plan view showing a communication passage 544′ of thecompliance plate 50′ according to the first comparative example, andcorresponds to FIG. 6. FIG. 8 is a sectional view taken along lineVIII-VIII shown in FIG. 7. The communication passage 544′ of FIGS. 7 and8 has a width narrower than that of the communication passage 544 ofFIG. 6. Specifically, a width W′ of the communication passage 544′ issmaller than a diameter M of the atmospheric vent HA, and the width W ofthe communication passage 544 is larger than the diameter M of theatmospheric vent HA.

As shown in FIGS. 7 and 8, as the width W′ of the communication passage544′ becomes smaller, the air in the opening portion 541 hardly entersand exits from the atmospheric vent HA via the communication passage 544when the flexible film 52 bends. Then, it becomes difficult to move theflexible film 52 and the effect of absorbing the pressure fluctuation ofthe liquid storage chamber SR is deteriorated. Depending on the printpattern, the amplitude of the pressure vibration of the liquid storagechamber SR increases to exceed the meniscus pressure resistance in thenozzles N, and the meniscus may be destroyed, so that ejection failuresuch as dot omission occurs.

For example, it is found that dot omission occurs due to insufficientabsorption of the pressure fluctuation of the liquid storage chamber SRin a print pattern in which solid ejection (when ejection duty is 100%),excitation (for example, case of repeating ejection (print) andnon-ejection (blank) alternately), and solid ejection are continuous.Here, the ejection duty means the ratio of the ejected ink amount withrespect to the maximum possible ink ejection amount per unit time.

FIG. 9 is a graph showing pressure transition of the liquid storagechamber SR in a specific print pattern such as the occurrence of dotomission due to insufficient absorption of the pressure fluctuation ofthe liquid storage chamber SR. The vertical axis of FIG. 9 is pressure(negative pressure) and the horizontal axis is time. As shown in FIG. 9,since the ejection amount of ink is large in the solid ejection, thepressure inside the nozzles N reduces abruptly due to the solidejection, the meniscus in the nozzles N is greatly pulled toward thepressure chambers SC side. Therefore, the pressure vibration caused bythe subsequent excitation cannot be absorbed, and the amplitude becomeslarge and exceeds the meniscus pressure resistance to cause the dotomission in the subsequent continuous solid ejection.

Therefore, in the present embodiment, it is easy for the air in theopening portion 541 to enter and exit from the atmospheric vent HA viathe communication passage 544 when the flexible film 52 bends bywidening the width W of the communication passage 544. Accordingly, themovement of the flexible film 52 is facilitated, and it is possible toincrease the effect of absorbing the pressure fluctuation of the liquidstorage chamber SR. When the movement of the flexible film 52 isfacilitated, the pressure fluctuation is absorbed by the movement of theflexible film 52 and the amplitude becomes smaller even if it is excitedas shown in FIG. 9, so that it does not exceed the meniscus pressureresistance. Accordingly, it is possible to suppress the occurrence ofthe dot omission in the subsequent continuous solid ejection.

However, as the width W of the communication passage 544 becomes wider,the flexible film 52 easily bends inside the communication passage 544unless the flexible film 52 exposed into the communication passage 544is not supported, so that the sealing property between the flow passagemember 32 and the flexible film 52 around the liquid storage chamber SRis deteriorated.

FIGS. 10 to 12 are views showing a configuration of a compliance plate50″ according to a second comparative example of the first embodiment.FIG. 10 is a plan view showing a configuration of a communicationpassage 544″ of the compliance plate 50″ according to the secondcomparative example, and corresponds to FIG. 7. FIG. 11 is a sectionalview taken along line XI-XI in FIG. 10, and FIG. 12 is a sectional viewtaken along line XII-XII shown in FIG. 10. The width W of thecommunication passage 544″ of the second comparative example shown inFIGS. 11 and 12 is wider than the width W′ of the communication passage544′ of the first comparative example shown in FIG. 7, and the same asthe width W of the communication passage 544 of the first embodimentshown in FIG. 6.

As the width W becomes wider as the communication passage 544″ of FIGS.10 to 12, the flexible film 52 is easily bent into the communicationpassage 544 when the flow passage member 32, the flexible film 52, andthe support plate 54 are laminated at the time of manufacturing theliquid ejecting head 20 unless the flexible film 52 exposed into thecommunication passage 544 is not supported. Therefore, as white arrowsshown in FIGS. 11 and 12, since the portion of the flexible film 52exposed to the communication passage 544 is away from the flow passagemember 32 and becomes hard to adhere, the sealing property between theflow passage member 32 and the flexible film 52 around the liquidstorage chamber SR is deteriorated. When the sealing property isdeteriorated, leak of ink occurs as shown in black arrows of FIG. 12,which may cause problems such as leak of the ink of the liquid storagechamber SR to the atmospheric vent HA. In the present embodiment, bysupporting the flexible film 52 exposed to the communication passage 544with a support portion 545 as shown in FIG. 6, it is possible tosuppress the deterioration of the sealing property between the flowpassage member 32 and the flexible film 52 around the liquid storagechamber SR.

Operations and effects of the compliance plate 50 of the presentembodiment will be described in detail with reference to the drawings.FIGS. 13 to 15 are explanatory views of operations of the complianceplate 50 of the present embodiment. FIG. 13 is a plan view of thecommunication passage 544, and corresponds to FIG. 6. FIG. 14 is asectional view taken along line XIV-XIV shown in FIG. 13, and FIG. 15 isa sectional view taken along line XV-XV shown in FIG. 13. The flowpassage member 32 and the fixation plate 56 are omitted in FIG. 13. Asshown in FIG. 13 to FIG. 15, the support portion 545 that supports theflexible film 52 exposed to the communication passage 544 is provided inthe first embodiment. The support portion 545 of FIG. 13 is formed of aplurality of island portions provided in the communication passage 544.A case of constituting the support portion 545 with two island portionsis exemplified in FIG. 13. Each of the island portions is provideddiscontinuously from the support plate 54, and protrudes toward the flowpassage member 32 from the fixation plate 56 to support the flexiblefilm 52. Each of the island portions of the present embodiment is acylindrical member having a thickness from the fixation plate 56 to theflexible film 52, and is fixed to both the flexible film 52 and thefixation plate 56 by an adhesive and the like. As shown in FIG. 14, eachof the island portions of the present embodiment is aligned in astraight line passing through the center of the communication passage544 and extending along the Y direction.

As shown in FIGS. 14 and 15, according to the configuration of thepresent embodiment, even if the width W of the communication passage 544is widened, it is possible to support the portion of the flexible film52 exposed to the communication passage 544 with the support portion 545in an attachment direction (negative side of the Z direction) to theflow passage member 32. Therefore, since bending of the flexible film 52into the communication passage 544 can be suppressed when laminating theflow passage member 32, the flexible film 52, and the support plate 54at the time of manufacturing the liquid ejecting head 20, it is possibleto suppress the deterioration of the sealing property between the flowpassage member 32 and the flexible film 52 around the liquid storagechamber SR.

As shown in FIG. 13, in the present embodiment, the width W (width inthe X direction in a plan view from the Z direction) of the crosssection of the communication passage 544 that intersects with thedirection (Y direction) in which the communication passage 544 extendsis larger than the diameter M of the atmospheric vent HA. Accordingly,compared with the case of FIG. 7 where the width W of the communicationpassage 544 is smaller than the diameter M of the atmospheric vent HA,the air resistance in the extending direction of the communicationpassage 544, that is, a direction (Y direction) through which the airpasses can be reduced. Therefore, the movement of the flexible film 52is facilitated, and it is possible to increase the effect of absorbingthe pressure fluctuation of the liquid storage chamber SR. Furthermore,in a plan view from the Z direction, by setting the width W of thecommunication passage 544 to be ½ or more of the maximum width Wmax(maximum width in a plan view from the Z direction in the X direction)of the opening portion 541 in a cross section of the communicationpassage 544 that intersects with the direction (Y direction) in whichthe communication passage 544 extends, it is possible to reduce the airresistance inside the communication passage 544 in the direction inwhich the communication passage 544 extends.

As shown in FIG. 14, in a cross section P of the communication passage544 that intersects with the direction (Y direction) in which thecommunication passage 544 extends, the area of the portion occupied bythe support portion 545 is smaller than the area of the other portions(area of a portion through which the air passes). With thisconfiguration, the air resistance caused by the support portion 545 canbe reduced. Therefore, since the air in the opening portion 541 wherethe flexible film 52 bends becomes easy to enter and exit from theatmospheric vent HA via the communication passage 544, the movement ofthe flexible film 52 of the compliance region A exposed to the openingportion 541 is facilitated, so that it is possible to increase theeffect of absorbing the pressure fluctuation of the liquid storagechamber SR. According to the present embodiment, it is possible toincrease the sealing property between the flow passage member 32 and theflexible film 52 around the liquid storage chamber SR while increasingthe effect of absorbing the pressure fluctuation of the liquid storagechamber SR.

The two island portions constituting the support portion 545 of thepresent embodiment are disposed side-by-side in the direction (Ydirection) in which the communication passage 544 extends toward theatmospheric vent HA. With this configuration, since the plurality ofisland portions overlap seen from the Y direction, the resistance in thedirection in which the communication passage 544 extends, that is, thedirection through which the air passes the communication passage 544toward atmospheric vent HA can be reduced.

A case where each of the island portions constituting the supportportion 545 of FIG. 13 is fixed to both the flexible film 52 and thefixation plate 56 by an adhesive is exemplified. However, the inventionis not limited thereto, and each of the island portions may be fixed toeither one of the flexible film 52 and the fixation plate 56 by anadhesive and the like, and may not be fixed to the other one. Forexample, in a first modification example shown in FIG. 16, a case whereeach of the island portions constituting the support portion 545 adheresand is fixed to the flexible film 52 is exemplified. FIG. 16 is asectional view of the compliance plate 50 of the first modificationexample, and corresponds to FIG. 14. Even with configuration of FIG. 16,since it is possible to suppress the flexible film 52 bending into thecommunication passage 544, the deterioration of the sealing propertybetween the flow passage member 32 and the flexible film 52 around theliquid storage chamber SR can be suppressed. In the configuration ofFIG. 16, the thickness h of each of the island portions is thinner thanthe thickness H of the support plate 54, and a gap is formed between thefixation plate 56 and the island portion. In the configuration of FIG.16, since it is possible to reduce the thickness h of each of the islandportions, it is possible to reduce the area of a portion occupied by thesupport portion 545 in the cross section P of the communication passage544 than the case of fixing each of the island portions to both theflexible film 52 and the fixation plate 56. Therefore, the airresistance by the support portion 545 can be reduced.

A case where each of the island portions constituting the supportportion 545 of FIG. 13 is separate from the fixation plate 56 isexemplified. However, the invention is not limited thereto, and forexample, each of the island portions may be formed integrally with thefixation plate 56 as a second modification example shown in FIG. 17.FIG. 17 is a sectional view of the compliance plate 50 according to thesecond modification example, and corresponds to FIG. 14. Each of theisland portions of FIG. 17 protrudes toward the flow passage member 32from the fixation plate 56 and supports the flexible film 52. Asdescribed above, the case where each of the island portions is formedintegrally with the fixation plate 56, each of the island portions mayor may not adhere to the flexible film 52. In such a configuration,since the bending of the flexible film 52 into the communication passage544 can be suppressed, the deterioration of the sealing property betweenthe flow passage member 32 and the flexible film 52 around the liquidstorage chamber SR can be suppressed. Furthermore, not only the islandportions, but also the support plate 54 may be formed integrally withthe fixation plate 56. Even with such a configuration, it is possible tosuppress the flexible film 52 from bending into the communicationpassage 544.

The number, arrangement, and shape (such as length, width, outer shape,thickness, size) of the island portions constituting the support portion545 are not limited to the examples of the present embodiment. Forexample, the number of the each of the island portions may be increasedto reduce the diameter as in a third modification example shown in FIG.18. FIG. 18 is a plan view of the compliance plate 50 according to thethird modification example, and corresponds to FIG. 13. In FIG. 18, acase where five island portions are disposed inside the communicationpassage 544, and the diameter of each of the island portions is madesmaller than the island portion of FIG. 13 is exemplified. By increasingthe number of the island portions, it is possible to increase the effectthat can suppress the flexible film 52 from bending into thecommunication passage 544. Furthermore, by reducing the diameter of theisland portion, the air resistance by the support portion 545 can bereduced.

The shape of the communication passage 544 is not limited to the exampleof the first embodiment. The shape of the communication passage 544 maybe changed according to the shape of the liquid storage chamber SR. Forexample, in the liquid storage chamber SR of a fourth modificationexample shown in FIG. 19, the length of the end portion (end portion inthe Y direction) is longer than the liquid storage chamber SR in FIG. 6.It is possible to increase the number of the nozzles N arranged at theend portion by increasing the length of the end portion of the liquidstorage chamber SR. FIG. 19 is a plan view of the compliance plate 50according to the fourth modification example, and corresponds to FIG.13.

Since the end portion of the liquid storage chamber SR in FIG. 19projects to the atmospheric vent HA side from the end portion of theliquid storage chamber SR in FIG. 6, the width W of the communicationpassage 544 and the shape of the liquid storage chamber SR is partlydifferent. In the communication passage 544 of FIG. 19, a width W1 inthe Y direction of the portion overlapping the liquid storage chamber SRin the X direction is smaller than a width W2 in the Y direction of theportion not overlapping with the liquid storage chamber SR in the Xdirection. Therefore, the support portion 545 in FIG. 19 is constitutedby the island portions arranged at the center of the width W1 and thecenter of the width W2 of the communication passage 544 one by one. Withsuch a configuration, while the air resistance by the support portion545 is reduced at each portion of the widths W1 and W2, thedeterioration of the sealing property between the flow passage member 32and the flexible film 52 around the liquid storage chamber SR can besuppressed. However, also in the configuration of FIG. 19, the number,arrangement, and shape (such as length, width, external shape,thickness, size) of the island portions are not limited to those shownin the drawings.

In FIG. 13, the case where the support portion 545 is constituted by theisland portions has been exemplified. However, the invention is notlimited thereto, and the support portion 545 may be composed of a railportion. FIGS. 20 and 21 are diagrams showing the configuration of thecompliance plate 50 according to a fifth modification example, and thecase where the support portion 545 is composed of a rail portion will beexemplified. FIG. 20 is a plan view showing the compliance plate 50according to the fifth modification example, and FIG. 21 is a sectionalview taken along line XXI-XXI in FIG. 20. As shown in FIGS. 20 and 21,the support portion 545 of the fifth modification example is constitutedby a plurality of cantilever-shaped rail portions.

Each rail portion projects into the communication passage 544 from oneside of two opposite side surfaces (negative side surface of the Xdirection and the positive side surface) of the communication passage544. Each rail portion is connected to the side surface on one side ofthe communication passage 544 and is separated from the side surfaceopposed thereto. A thickness h′ of each rail portion is thinner than thethickness H of the support plate 54, and a gap is formed between therail portion and the fixation plate 56. Therefore, the area of theportion occupied by the support portion 545 in the cross section P ofthe communication passage 544 can be reduced, so that the air resistanceby the support portion 545 can be reduced. In the fifth modificationexample, the case where three rail portions protrude one by onealternately from the two opposite side surfaces of the communicationpassage 544 is exemplified, but the invention is not limited thereto.The rail portions may protrude alternately by two or more, or, they maynot be alternately provided. The rail portion may protrude from only oneof the two opposing side surfaces of the communication passage 544. Thenumber, the arrangement and the shape (such as length, width, outershape, thickness, size) of the rail portion are not limited to thoseillustrated in drawings.

Second Embodiment

A second embodiment of the invention will be described. For the elementshaving the same operations and functions as those in the firstembodiment in the following examples, the reference numerals used in thedescription of the first embodiment are used, and the detaileddescription thereof is appropriately omitted. In the first embodiment, acase where one liquid storage chamber SR is continuous in the Ydirection is exemplified. However, in the second embodiment, a casewhere a plurality of liquid storage chambers SR are arranged side byside in the Y direction will be exemplified.

FIG. 22 is a plan view showing a compliance plate 50 according to thesecond embodiment. In FIG. 22, three liquid storage chambers SR arearranged side by side in the Y direction. In the support plate 54 ofFIG. 22, the opening portion 541 in which the flexible film 52 isexposed is formed in the compliance region A overlapping each of theliquid storage chambers SR in a plan view from the Z direction. The mostpositive side opening portion 541 in the Y direction communicates withthe atmospheric vent HA via a first communication passage 544A. Eachopening portion 541 of the support plate 54 communicates via a secondcommunication passage 544B disposed in a region B (region around eachliquid storage chamber SR for sealing the flow passage member 32 and theflexible film 52) between the opening portions 541. Accordingly, eachopening portion 541 communicates with the atmospheric vent HA via thefirst communication passage 544A and the second communication passage544B, so that the movement of the flexible film 52 in the complianceregion A corresponding to each liquid storage chamber SR is facilitated.As described above, the first communication passage 544A and the secondcommunication passage 544B function as a communication passage thatcommunicates the opening portion 541 with the atmosphere.

In the configuration of FIG. 22, by increasing the width W not only forthe first communication passage 544A but also for the secondcommunication passage 544B, when the flexible film 52 bends, the air inthe opening portion 541 can easily enter and exit from the atmosphericvent HA via each of the communication passages 544A and 544B.Specifically, in a plan view from the Z direction, the width W (width inthe X direction) of each of the communication passages 544A and 544B islarger than the diameter M of the atmospheric vent HA. Accordingly, ascompared with the case where the width W of each communication passages544A and 544B is smaller than the diameter M of the atmospheric vent HA,the air resistance in each communication passages 544A and 544B can bereduced. Therefore, the movement of the flexible film 52 is facilitated,and it is possible to increase the effect of absorbing the pressurefluctuation of the liquid storage chamber SR. In the plan view from theZ direction, by setting the width W of each of the communicationpassages 544A and 544B to be ½ or more of the maximum width Wmax(maximum width in plan view from the Z direction in the X direction) ofthe opening portion 541 in the cross section of each of thecommunication passages 544A and 544B that intersects with the Ydirection, it is possible to remarkably reduce the air resistance ineach of the communication passages 544A and 544B.

In the configuration of FIG. 22, not only the first communicationpassage 544A but also the second communication passage 544B, theflexible film 52 exposed in each of the communication passages 544A and544B is supported by the support portion 545. The support portion 545 inFIG. 22 is exemplified by a case where it is constituted by theplurality of island portions. However, the support portion 545 of FIG.22 may be composed of a rail portion as shown in FIG. 20. The number,the arrangement, and the shape (such as length, width, outer shape,thickness, size) of the island portions and the rail portion are notlimited to those illustrated in drawings. As described above, even ifthe width W of each of the communication passages 544A and 544B isincreased, it is possible to suppress the bending of the flexible film52 exposed into each of the communication passages 544A and 544B bydisposing the support portion 545 in each of the communication passages544A and 544B, so that the deterioration of the sealing property betweenthe flow passage member 32 and the flexible film 52 around each liquidstorage chamber SR can be suppressed.

Moreover, in the configuration of FIG. 22, not only for the firstcommunication passage 544A but also for the second communication passage544B, the area of the portion occupied by the support portion 545 issmaller than the area of the other portions (area of the portion throughwhich air passes) in the cross section including the support portion 545among the cross sections of each of the communication passages 544A and544B intersecting with the Y direction in which the each ofcommunication passages 544A and 544B extends. The air resistance by thesupport portion 545 can be reduced, so that the air in each openingportion 541 in which the flexible film 52 bends can easily enter andexit from the atmospheric vent HA via each of the communication passages544A and 544B. Accordingly, the movement of the flexible film 52 in thecompliance region A exposed in the opening portion 541 is facilitated,so that the effect of absorbing the pressure fluctuation of the liquidstorage chamber SR can be increased. According to the second embodimentas well, as in the first embodiment, the deterioration of the sealingproperty between the flow passage member 32 and the flexible film 52around the liquid storage chamber SR can be suppressed while increasingthe effect of absorbing the pressure fluctuation of the liquid storagechamber SR.

In FIG. 22, a configuration in which both the communication passages544A and 544B are formed is exemplified, but only the communicationpassage 544B may be formed in the support plate 54. That is, thecommunication passage 544A may be omitted.

Modification Examples

The aspects and the embodiments exemplified above can be variouslymodified. Specific modes of modification are exemplified below. Two ormore aspects randomly selected from the following examples and theabove-described aspects can be appropriately merged within a range notinconsistent with each other.

(1) In the above-described embodiment, the serial head that reciprocallyreciprocates the carriage 18 installed on the liquid ejecting head 20along the X direction is exemplified. However, the invention is alsoapplicable to a line head in which the liquid ejecting head 20 isdisposed over the entire width of the medium 11.

(2) In the above-described embodiment, the piezoelectric type liquidejecting head 20 using the piezoelectric element that applies themechanical vibration to the pressure chamber is exemplified. However, itis also possible to adopt a thermal type liquid ejecting head using aheat generating element which generates bubbles inside the pressurechamber by heating.

(3) The liquid ejecting apparatus 10 exemplified in the above-describedembodiment can be adopted for various apparatuses such as a facsimileapparatus and a copying machine in addition to the apparatus dedicatedfor printing. The application of the liquid ejecting apparatus 10 of theinvention is not limited to printing. For example, a liquid ejectingapparatus that ejects a solution of a coloring material is used as amanufacturing apparatus that forms a color filter, an organic electroluminescence (EL) display, an FED (surface emitting display), and thelike of a liquid crystal display apparatus. A liquid ejecting apparatusfor ejecting a solution of a conductive material is used as amanufacturing apparatus for forming wirings and electrodes of a wiringsubstrate. It is also used as a chip manufacturing apparatus forejecting a solution of a bioorganic matter as a kind of liquid.

This application claims priority to Japanese Patent Application No.2017-250347 filed on Dec. 27, 2017 and Japanese Patent Application No.2018-155602 filed on Aug. 22, 2018. The entire disclosures of JapanesePatent Application Nos. 2017-250347 and 2018-155602 are herebyincorporated herein by reference.

What is claimed is:
 1. A flow passage structure comprising: a flowpassage member that constitutes a portion of a wall surface of a liquidstorage chamber; a flexible film that is laminated on the flow passagemember and constitutes a portion of the wall surface of the liquidstorage chamber; a sealing body that is laminated on a side opposite tothe flow passage member with the flexible film interposed therebetweenand forms a space in which the flexible film is exposed; communicationpassages that are formed in a region around the liquid storage chamberin the sealing body and causes the space to communicate with anatmosphere in a case where the sealing body is seen in a plan view froma direction in which the flow passage member and the flexible film arelaminated; and a support portion that supports the flexible film in thecommunication passage.
 2. The flow passage structure according to claim1, wherein, in a cross section including the support portion among crosssections of the communication passages that intersect with a directionin which the communication passage extends, an area of a portionoccupied by the support portion is smaller than an area of the otherportions.
 3. The flow passage structure according to claim 2, whereinthe communication passage communicates with the atmosphere via anatmospheric vent distanced from the liquid storage chamber, and whereina width of the communication passage in the cross section of thecommunication passage that intersects with the direction in which thecommunication passage extends is larger than a diameter of theatmospheric vent.
 4. The flow passage structure according to claim 3,wherein the atmospheric vent is a through-hole formed in the flexiblefilm.
 5. The flow passage structure according to claim 4, wherein theatmospheric vent is formed in the flow passage member.
 6. The flowpassage structure according to claim 5, wherein the support portion isan island portion that is disposed in the communication passage.
 7. Theflow passage structure according to claim 6, wherein a plurality of theisland portions are arranged side by side in a direction in which thecommunication passage extends.
 8. The flow passage structure accordingto claim 7, wherein the support portion is a rail portion that projectsinto the communication passage from one or both sides of side surfacesof the communication passage facing each other.
 9. The flow passagestructure according to claim 8, wherein the width of the communicationpassage is ½ or more of a maximum width of a cross section of the spaceamong cross sections of the communication passages that intersect with adirection in which the communication passage extends.
 10. The flowpassage structure according to claim 9, wherein the sealing body isconstituted of a support plate that is laminated on the flexible filmand a fixation plate that is laminated on the support plate on a sideopposite to the flexible film, and wherein the support portion supportsthe flexible film that protrudes from the fixation plate toward theflexible film.
 11. The flow passage structure according to claim 10,wherein, in a plan view of the sealing body, the communication passageis formed in a region corresponding to one end of the liquid storagechamber in the sealing body.
 12. The flow passage structure according toclaim 11, wherein a plurality of the liquid storage chambers are formedin the flow passage member, wherein a plurality of the spaces eachcorresponding to the plurality of liquid storage chambers are formed inthe sealing body, and wherein the communication passage communicateswith each of the spaces.
 13. A liquid ejecting head comprising: the flowpassage structure according to claim 1; and a nozzle that ejects liquidsupplied from the liquid storage chamber.
 14. A liquid ejecting headcomprising: the flow passage structure according to claim 12; and anozzle that ejects liquid supplied from the liquid storage chamber. 15.The flow passage structure according to claim 1, wherein thecommunication passage communicates with the atmosphere via anatmospheric vent distanced from the liquid storage chamber, and whereina width of the communication passage in the cross section of thecommunication passage that intersects with the direction in which thecommunication passage extends is larger than a diameter of theatmospheric vent.
 16. The flow passage structure according to claim 1,wherein the width of the communication passage is ½ or more of a maximumwidth of a cross section of the space among cross sections of thecommunication passages that intersect with a direction in which thecommunication passage extends.
 17. The flow passage structure accordingto claim 15, wherein the width of the communication passage is ½ or moreof a maximum width of a cross section of the space among cross sectionsof the communication passages that intersect with a direction in whichthe communication passage extends.
 18. The flow passage structureaccording to claim 1, wherein the sealing body is constituted of asupport plate that is laminated on the flexible film and a fixationplate that is laminated on the support plate on a side opposite to theflexible film, and wherein the support portion supports the flexiblefilm that protrudes from the fixation plate toward the flexible film.19. The flow passage structure according to claim 17, wherein thesealing body is constituted of a support plate that is laminated on theflexible film and a fixation plate that is laminated on the supportplate on a side opposite to the flexible film, and wherein the supportportion supports the flexible film that protrudes from the fixationplate toward the flexible film.
 20. A liquid ejecting apparatuscomprising: the liquid ejecting head according to claim 13; and acontrol device that causes the liquid ejecting head to eject liquid.